JP6666173B2 - Laser processing equipment - Google Patents

Description

  The present invention relates to a laser processing device.

  A laser beam is applied to a semiconductor wafer (hereinafter, simply referred to as a “wafer”) on which a device such as an IC (Integrated Circuit) is formed by a laser processing apparatus, and a modified layer is formed along a line to be divided. A processing method of dividing an individual device as a fracture starting point is known. The laser processing apparatus can form an intermittent modified layer by switching between laser beam irradiation and irradiation stop. Therefore, the laser processing apparatus can process a wafer having discontinuous scheduled dividing lines (for example, see Patent Documents 1 and 2).

JP 2010-123723 A JP-A-2005-020177

  A plurality of devices partitioned by the planned dividing lines are arranged on the wafer. When the starting point or the end point of the modified layer extending in the direction along a certain dividing line exceeds the modifying layer extending in the direction along the intersecting dividing line, the wafer is broken into individual devices. However, there is a problem that the modified layer extending beyond the modified layer extending in the intersecting direction causes a crack to propagate in the device region, and the device is divided. Therefore, it is necessary to set the irradiation position of the laser beam with high accuracy.

  Conventionally, processing conditions are set so that a laser beam is applied to the vicinity of the center of the planned dividing line displayed on the display means. However, even if the set processing conditions are displaced in units of microns, the above-described problem occurs, and thus it is difficult to set the processing conditions.

  When the starting point or the end point of the modified layer is slightly away from the modified layer extending in the crossing direction, the leakage light of the laser beam does not reach the device area, and the effect of reducing the possibility of damaging the device is reduced. I got the knowledge that there is.

  As described above, there has been a demand to set the position of the start point or the end point of the modified layer with high accuracy with respect to the modified layer extending in the crossing direction.

  The present invention has been made in view of the above, and an object of the present invention is to provide a laser processing apparatus capable of setting the positions of a starting point and an ending point of a modified layer with high accuracy.

In order to solve the above-described problems and achieve the object, a laser processing apparatus according to the present invention includes a first dividing line extending in a first direction and a second dividing line extending in a direction intersecting the first direction. Are set, and devices are formed in an area defined by the first planned dividing line and the second planned dividing line, and the first planned dividing line is formed intermittently. A wafer provided with a region where the start point or the end point of the line is connected to the second scheduled line is irradiated with a laser beam to form a modified layer along the first scheduled line and the second scheduled line. A laser processing apparatus formed inside the wafer, comprising: a chuck table for holding the wafer on a holding surface; and a laser beam having a wavelength transmissive to the wafer, the wafer being held on the chuck table. A laser beam application means for applying a Heather beam processing conditions for processing a moving means for relatively moving the chuck table and the laser beam application means, imaging means for imaging the wafer held on the chuck table, the wafer A storage means for storing the formation position of the modified layer, which is a position where the modified layer is to be formed , as the processing condition; and Display means for displaying the formation position of the modified layer stored in the storage means as a planned processing line , wherein the display means is a start point or an end point of the first planned division line imaged by the imaging means . Displays an area connected to the second planned dividing line, and displays the area where the modified layer is to be formed and the first planned dividing line and the second planned dividing line. If there is any even without reforming layer is planned processing line along the position that is to be formed of the first taken by the image pickup means dividing lines and the second division line and the The position of the starting point or the end point of the modified layer formed on the first planned dividing line or the second planned dividing line is displayed so as to be superimposed on at least one of the first planned dividing line and the second planned dividing line. Is set corresponding to the position of the modified layer formed on the line to be divided.
In the laser processing apparatus, the display means may display the set scheduled processing line, and may be capable of correcting the start point or the end point of the set scheduled processing line.
In the laser processing apparatus, the display means may irradiate the laser beam irradiating means with the laser beam irradiating means on the second planned division line when the planned processing line is displayed overlapping the first planned division line. A hairline, which is a target line when designating a position, may be displayed so as to overlap the second scheduled division line.

  According to the laser processing apparatus of the present invention, the positions of the start point and the end point of the modified layer can be set with high accuracy.

FIG. 1 is a perspective view showing a laser processing apparatus according to the embodiment. FIG. 2 is a perspective view showing a wafer processed by the laser processing apparatus according to the embodiment. FIG. 3 is a plan view showing a wafer processed by the laser processing apparatus according to the embodiment. FIG. 4A is a schematic diagram illustrating a procedure for setting a starting point of the modified layer in the laser processing apparatus according to the embodiment. FIG. 4B is a schematic view illustrating a procedure for setting an end point of the modified layer in the laser processing apparatus according to the embodiment. FIG. 5 is a schematic diagram illustrating a procedure for setting a start point or an end point of the modified layer extending in a direction intersecting the modified layer by the laser processing apparatus according to the embodiment. FIG. 6 is a schematic diagram illustrating a modified layer set by a conventional laser processing apparatus.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Further, the configurations described below can be appropriately combined. In addition, various omissions, substitutions, or changes in the configuration can be made without departing from the spirit of the present invention.

  FIG. 1 is a perspective view showing a laser processing apparatus according to the embodiment. FIG. 2 is a perspective view showing a wafer processed by the laser processing apparatus according to the embodiment. FIG. 3 is a plan view showing a wafer processed by the laser processing apparatus according to the embodiment. FIG. 4A is a schematic diagram illustrating a procedure for setting a starting point of the modified layer in the laser processing apparatus according to the embodiment. FIG. 4B is a schematic view illustrating a procedure for setting an end point of the modified layer in the laser processing apparatus according to the embodiment. FIG. 5 is a schematic diagram illustrating a procedure for setting a start point or an end point of the modified layer extending in a direction intersecting the modified layer by the laser processing apparatus according to the embodiment.

  A laser processing apparatus 1 according to the present embodiment will be described with reference to FIG. The laser processing apparatus 1 irradiates the wafer W held on the chuck table 10 with a laser beam, and places the modified layer along the first planned division line L1 and the second planned division line L2 inside the wafer W. Form.

  As shown in FIG. 2, the surface W of the wafer W is attached to the surface of the adhesive tape T mounted on the annular frame F. On the surface Wa of the wafer W, a plurality of devices D are formed in a region partitioned by the plurality of planned dividing lines L. In the present embodiment, the wafer W includes devices D having different sizes and shapes. More specifically, the wafer W is divided into a first division line L1 extending in the X-axis direction (first direction) and a second division extending in the Y-axis direction (second direction) intersecting the X-axis direction. The scheduled line L2 is set. The wafer W includes an area where the start point PS or the end point PE of the intermittently formed first division line L1 is connected to the second division line L2. Such a wafer W is divided into individual devices D by being processed by the laser processing apparatus 1 to form a modified layer. In the present embodiment, the wafer W to be processed by the laser processing apparatus 1 is a disk-shaped semiconductor wafer or optical device wafer whose base material is silicon, sapphire, gallium, or the like.

  Returning to FIG. 1, the laser processing apparatus 1 includes a substantially rectangular parallelepiped main body 2, a wall 3 erected upward from the rear side of the main body 2, and a support column 4 projecting forward from the wall 3. And

  As shown in FIG. 1, the laser processing apparatus 1 includes a chuck table 10 for holding a wafer W, an X-axis moving unit 20 for relatively moving the chuck table 10 and the laser beam irradiation unit 50 in the X-axis direction, and a chuck table 10. Y-axis moving means 30 for relatively moving the laser beam irradiating means 50 in the Y-axis direction, rotating means 40 for rotating the chuck table 10 around a central axis parallel to the Z-axis direction, and a wafer held by the chuck table 10 A laser beam irradiating unit 50 that irradiates a pulse laser beam to W to perform laser processing, an imaging unit 60, and a control unit 100 are provided.

  The chuck table 10 has a holding surface 10a for holding the wafer W. The holding surface 10a holds the wafer W attached to the opening of the frame F via the adhesive tape T. The holding surface 10a has a disk shape made of a porous ceramic or the like, and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown). The holding surface 10a sucks and holds the placed wafer W via the adhesive tape T. Around the chuck table 10, a plurality of clamp portions 11 for holding the frame F around the wafer W are arranged.

  The X-axis moving means 20 is a processing feed means for processing the chuck table 10 in the X-axis direction by moving the chuck table 10 in the X-axis direction. The X-axis moving means 20 supports a ball screw 21 provided rotatably about the axis, a pulse motor 22 for rotating the ball screw 21 about the axis, and the chuck table 10 so as to be movable in the X-axis direction. And a guide rail 23.

  The Y-axis moving means 30 is indexing means for indexing and feeding the chuck table 10 by moving the chuck table 10 in the Y-axis direction. The Y-axis moving means 30 supports the ball screw 31 provided rotatably about the axis, the pulse motor 32 for rotating the ball screw 31 about the axis, and the chuck table 10 so as to be movable in the Y-axis direction. And a guide rail 33.

  The rotating means 40 rotates the chuck table 10 about a central axis parallel to the Z-axis direction. The rotating means 40 is disposed on the moving table 12 which is moved in the X-axis direction by the X-axis moving means 20.

  The laser beam irradiation means 50 performs laser processing on the wafer W held on the chuck table 10. More specifically, the laser beam irradiating unit 50 irradiates the wafer W held on the chuck table 10 with laser light having a wavelength that is transparent to the wafer W to form a modified layer inside the wafer W. The laser beam irradiating unit 50 includes an oscillating unit that oscillates a laser beam and a condensing unit that condenses the laser beam at a desired position on the wafer W. The laser beam irradiation means 50 is attached to the tip of the support column 4.

  The imaging unit 60 is for imaging the wafer W held on the chuck table 10 from above, and is disposed at a position parallel to the laser beam irradiation unit 50 in the X-axis direction. The imaging means 60 is attached to the tip of the support column 4. The imaging unit 60 has an imaging element that detects light in an infrared region that is not easily absorbed by the wafer W. The imaging unit 60 outputs the captured image to the control unit 100.

  The control unit 100 controls each of the above-described components to cause the laser processing apparatus 1 to perform a laser processing operation on the wafer W. Control means 100 includes a computer system. The control means 100 includes an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as a ROM (read only memory) or a RAM (random access memory), and an input / output interface device. And

  The arithmetic processing device of the control means 100 performs arithmetic processing according to a computer program stored in the storage device, and sends a control signal for controlling the laser processing device 1 to the laser processing device 1 via the input / output interface device. Is output to the above-mentioned components. Further, the control means 100 is connected to a display panel (display means) 110 composed of a liquid crystal display device or the like for displaying a state of a processing operation, an image and the like, and an input means used when an operator registers processing content information and the like. Have been. The input unit includes at least one of a touch panel provided on the display panel 110, a keyboard, and the like.

  The control unit 100 includes a storage unit (storage unit) 101, a mark control unit 102, a planned processing line calculation unit 103, and a display panel 110. The control unit 100 displays a captured image of the area 111 </ b> A adjusted to the display screen 111 of the display panel 110 based on the captured image captured by the imaging unit 60.

  The storage unit 101 stores programs and data necessary for processing in the control unit 100. The storage unit 101 stores processing conditions for processing the wafer W. The processing condition is information on the position where the modified layer is to be formed, in other words, the position LK at which the modified layer is to be formed, which is the position to be irradiated with the laser beam. In the present embodiment, the formation position LK of the modified layer is set by the XY coordinates on the wafer W between the start point and the end point of the modified layer. In other words, the formation position LK of the modified layer is set as the planned processing line K connecting the start point and the end point of the modified layer.

  The mark control unit 102 causes the display panel 110 to display the mark M and the mark MP over the captured image. The mark M is a rectangular frame and surrounds the mark MP. The mark MP has a cross shape positioned at the center of the mark portion M. In the present embodiment, the formation position LK can be set by moving the mark MP to a desired position on the captured image displayed on the display panel 110. The mark control unit 102 converts the position of the mark MP on the captured image displayed on the display panel 110 into XY coordinates on the wafer W.

  The planned processing line calculation unit 103 causes the display panel 110 to display a planned processing line K, which is a virtual line, based on the modified layer formation position LK stored in the storage unit 101. More specifically, the planned processing line calculation unit 103 already forms the modified layer when displaying the area where the start point PS or the end point PE of the first planned division line L1 is connected to the second planned division line L2. When there is at least one of the first planned division line L1 and the second planned division line L2 whose positions are stored, the planned processing line K is overlapped along the position where the modified layer is to be formed. To display. The planned processing line calculation unit 103 includes the XY coordinate area 111A of the wafer W corresponding to the captured image displayed on the display panel 110, including the modified layer formation position LK stored in the storage unit 101 as the processing condition. In such a case, the formation position LK of the modified layer is displayed on the display panel 110 as the planned processing line K over the captured image.

  The display panel 110 is a touch-type display panel. The display panel 110 displays a captured image of the wafer W held on the chuck table 10 captured by the imaging unit 60 based on a control signal from the control unit 100. The display panel 110 displays the mark M, the mark MP, and the planned processing line K together with the captured image. The display panel 110 can set the positions of the start point and the end point of the modified layer formed on the first scheduled division line L1 and the second scheduled division line L2. Further, the display panel 110 has already stored the position where the modified layer is formed when displaying the area where the start point PS or the end point PE of the first planned division line L1 is connected to the second planned division line L2. When there is at least one of the first planned division line L1 and the second planned division line L2, the planned processing line K is superimposed and displayed along the position where the modified layer is to be formed. In this case, the display panel 110 determines the position of the starting point or the end point of the modified layer formed on the first planned division line L1 or the second planned division line L2 by using the second planned division line L2 or the first planned division line. It can be set corresponding to the position of the modified layer formed on the line L1.

  Next, an alignment method of the laser processing apparatus 1 for setting the starting point and the end point of the modified layer using the laser processing apparatus 1 according to the present embodiment will be described. The alignment method of the laser processing apparatus 1 includes a wafer holding step, a first scheduled processing position setting step, and a second scheduled processing position setting step.

  Perform the wafer holding step. In the wafer holding step, the wafer W is held on the chuck table 10. More specifically, the front surface Wa of the wafer W attached to the opening of the frame F via the adhesive tape T is sucked and held on the holding surface 10a so that the back surface Wb of the wafer W is exposed facing upward.

  After executing the wafer holding step, a first scheduled processing position setting step is executed. In the first scheduled processing position setting step, the starting point and the ending point of the modified layer formed along the first dividing line L1 are registered.

  More specifically, first, the control unit 100 moves the chuck table 10 with the X-axis moving unit 20 and the Y-axis moving unit 30 to position the wafer W held on the chuck table 10 below the imaging unit 60. . Then, the control unit 100 causes the imaging unit 60 to image the wafer W. The imaging unit 60 outputs the captured image to the control unit 100. The control unit 100 causes the display panel 110 to display the captured image.

Then, the operator rotates the chuck table 10 to adjust the direction of the first scheduled division line L1 in parallel with the X-axis direction (processing feed direction), and then forms a key pattern (unique pattern) formed on the device D (not shown). Pattern). By reading the new wafer W key pattern held on the chuck table 10, indexing the position of the wafer W, it is possible to determine the position of forming the modified layer of the dividing line L. After that, while registering the distance from the registered key pattern, the start point of the first scheduled division line L1 is set as the start point of the modified layer. For example, the operator taps the start point PS of the first scheduled division line L1 displayed on the display panel 110. As shown in FIG. 4A, the control unit 100 enlarges and displays the periphery of the start point PS on the display screen 111 of the display panel 110 indicated by a rectangular frame in the figure. At this time, the mark section M and the mark MP are displayed on the display panel 110 so as to overlap the captured image. For the sake of explanation, the formation position LK of the modified layer formed in the direction along the first scheduled division line L1 is shown by a broken line. Then, while touching the display panel 110, the operator moves the mark MP until it coincides with the start point PS, as shown in FIG. 4B. Then, the operator sets the start point PS as the start point of the modified layer by touching a start point setting icon in a state where the mark MP matches the start point PS. The control unit 100 causes the mark control unit 102 to convert the position of the mark MP on the captured image into XY coordinates on the wafer W. Then, the control unit 100 causes the storage unit 101 to store the position of the starting point PS, which is the converted XY coordinates, as one of the processing conditions.

  Then, the operator sets the end point PE of the first scheduled division line L1 as the end point of the modified layer. For example, while touching the display panel 110, the operator moves the mark MP until the mark MP coincides with the end point PE. Then, the operator sets the end point PE as the end point of the modified layer by touching the end point setting icon in a state where the mark MP matches the end point PE. The control unit 100 causes the mark control unit 102 to convert the position of the mark MP on the captured image into XY coordinates on the wafer W. Then, the control unit 100 causes the storage unit 101 to store the position of the end point PE, which is the converted XY coordinates, as one of the processing conditions.

  Such a procedure is repeated along the first scheduled division line L1, and the operator sets the start point and the end point of the modified layer formed intermittently along the first scheduled division line L1. In this way, the intermittent scheduled processing line K extending in the direction along the first planned division line L1 is set and stored as the processing condition. Further, the same procedure is repeated for other divided lines extending in a direction parallel to the first divided line L1.

  After performing the first scheduled processing position setting step, a second scheduled processing position setting step is performed. In the second scheduled processing position setting step, the starting point and the ending point of the modified layer formed along the second scheduled dividing line L2 extending in a direction orthogonal to the first scheduled dividing line L1 are registered. In the present embodiment, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 are set to be slightly separated from each other. It will be described as an example.

  More specifically, first, the control means 100 causes the rotating means 40 to rotate the chuck table 10 by 90 °.

  Then, the operator rotates the chuck table 10 to adjust the direction of the second scheduled division line L2 to be parallel to the X-axis direction (machining feed direction), and then forms a key pattern (unique pattern) formed on the device D (not shown). Pattern). After that, while registering the distance from the registered key pattern, the start point of the second scheduled division line L2 is set as the start point of the modified layer in the same procedure as the start point of the first scheduled division line L1. Then, the operator sets the end point of the second scheduled division line L2 as the end point of the reformed layer in the same procedure as the end point of the first scheduled division line L1.

  In the second scheduled processing position setting step, as shown in FIG. 5, the control means 100 causes the planned processing line calculation unit 103 to display the set planned processing line K that intersects with the second planned division line L2 on the display panel. 110 is displayed. At this time, the display panel 110 displays a hairline H, which is a target line when designating the irradiation position of the laser beam by the laser beam irradiation unit 50 on the second scheduled division line L2. In other words, the display panel 110 displays the planned processing line K set in the first planned processing position setting step and the hairline H as the target line.

  For example, while the operator moves the mark MP from the start point to coincide with the end point, if the planned processing line K is displayed on the display panel 110 in the direction intersecting the second planned division line L2, the operator has already set the mark. Correct the start point or end point of the planned processing line K. For example, the operator taps the end point PE of the first planned division line L1 which is the intersection of the second planned division line L2 and the planned processing line K displayed on the display panel 110. Then, the operator moves the mark MP upward from the end point PE of the first scheduled division line L1 such that the end point PE of the first scheduled division line L1 is separated from the hairline H while performing a touch operation on the display panel 110. Let it. Then, the operator sets the corrected end point PE, for example, by touching an end point setting icon while the mark MP is positioned above the end point PE of the first scheduled division line L1. The control unit 100 causes the mark control unit 102 to convert the position of the mark MP on the captured image into XY coordinates on the wafer W. The control unit 100 causes the storage unit 101 to store the position of the end point PE, which is the converted XY coordinates.

  By repeating such processing along the second scheduled division line L2, the operator sets the start point and the end point of the modified layer formed intermittently along the second scheduled division line L2. Thus, the intermittent scheduled processing line K extending in the direction along the second scheduled division line L2 is set and stored as the processing condition. In addition, the operator corrects and sets the start point or the end point of the modified layer for all the planned processing lines K set in the direction intersecting the second planned division line L2. Further, the same procedure is repeated for other divided lines extending in a direction parallel to the second divided line L2.

  Alternatively, in the second scheduled processing position setting step, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 in the following manner May be set so as to be slightly separated from the modified layer to be formed.

  More specifically, when the operator sets the second planned division line L2 and the processing panel K is displayed on the display panel 110 in a direction that intersects the second planned division line L2, the operator sets the set processing plan. The start point or the end point of the second scheduled division line L2 is registered so as to be slightly away from the line K. For example, the operator taps the end point PE of the first planned division line L1 which is the intersection of the second planned division line L2 and the planned processing line K displayed on the display panel 110. Then, while touching the display panel 110, the operator moves the mark MP below the end point PE of the first scheduled division line L1. Then, the operator moves the mark MP to the start point along the second planned division line L2 while the mark MP is positioned below the end point PE of the first planned division line L1, and displays the start point setting icon. The start point PS is set by touching or the like. The control unit 100 causes the mark control unit 102 to convert the position of the mark MP on the captured image into XY coordinates on the wafer W. The control unit 100 causes the storage unit 101 to store the position of the starting point PS, which is the converted XY coordinates. Then, the operator moves the mark MP to the end point along the second scheduled division line L2, and sets the end point PE by touching an icon for setting the end point. The control unit 100 causes the mark control unit 102 to convert the position of the mark MP on the captured image into XY coordinates on the wafer W. The control unit 100 causes the storage unit 101 to store the position of the end point PE, which is the converted XY coordinates. Such a process is repeated along the second scheduled division line L2, and the operator moves the second scheduled division line slightly away from the modified layer formed in the direction along the first scheduled division line L1. A start point and an end point of the modified layer formed intermittently along the line L2 are set.

  As described above, the operator sets the start point and the end point of the modified layer along all the planned division lines L of the wafer W by the above-described alignment method. When the start point and the end point of all the modified layers of the wafer W are set, the step of forming the modified layer is performed.

  As described above, according to the present embodiment, as shown in FIG. 5, when displaying the area where the start point PS or the end point PE of the first planned division line L1 is connected to the second planned division line L2, If there is at least one of the first planned division line L1 and the second planned division line L2 in which the position where the modified layer is to be formed is already stored, the position along the position where the modified layer is to be formed is determined. The processing line K is displayed in an overlapping manner. In other words, the display panel 110 displays the planned processing line K set in the first planned processing position setting step and the hairline H as the target line. For this reason, the positions of the start point and the end point of the modified layer formed on the intermittent scheduled division line L can be easily and accurately set by using the planned processing line K and the hairline H as clues. it can. As described above, according to the present embodiment, the positions of the start point and the end point of the modified layer can be set with high accuracy.

  Here, for comparison, setting of the starting point and the ending point of the modified layer using the conventional laser processing apparatus will be described with reference to FIG. FIG. 6 is a schematic diagram illustrating a modified layer set by a conventional laser processing apparatus. In the conventional laser processing apparatus, the set processing line is not displayed on the display panel even if the division line stores the position where the modified layer is formed. For this reason, it is difficult for the operator to set the starting point and the ending point of the modified layer to be formed along each scheduled dividing line with the hairline as a clue. In addition, since the start point and the end point of the modified layer formed along each planned dividing line must be set individually for each planned dividing line, they are slightly separated from the modified layer extending in the intersecting direction. It is difficult to set the position. When setting is performed using such a conventional laser processing apparatus, a planned processing line extending in an intersecting direction, such as the planned processing line K1 and the planned processing line K2, may be set in a state of being largely separated. . In such a case, there is a possibility that the breaking failure is likely to occur and the division cannot be performed at the division planned line. Further, as in the case of the planned processing line K1 and the planned processing line K3, the planned processing line extending in the intersecting direction may be set in a state exceeding one of the planned processing lines. In such a case, when the wafer W is broken into individual devices, a crack may be developed in the device region and the device D may be divided.

  In contrast, according to the present embodiment, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 are different from each other. It can be set with high accuracy. In the present embodiment, for example, the start point or the end point of the modified layer extending in the direction along a certain planned dividing line is set to exceed the modified layer extending in the direction along the intersecting planned dividing line. Can be suppressed. Thus, in the present embodiment, when the wafer is broken into individual devices, it is possible to suppress the growth of cracks in the device region and the division of the device.

  Alternatively, in the present embodiment, for example, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 are connected at points. This makes it easy to perform accurate positioning. As described above, in the present embodiment, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 are connected at points. By setting so that, for example, even when the thickness of the wafer W is large, it is possible to form the modified layer at an appropriate position and divide the device D into the individual devices D without fail.

  Alternatively, in the present embodiment, for example, the modified layer formed in the direction along the first planned division line L1 and the modified layer formed in the direction along the second planned division line L2 are slightly separated from each other. Such setting can be facilitated. As described above, in the present embodiment, by setting the modified layers slightly apart from each other, even if leakage light of the laser beam occurs, the influence on the adjacent device region can be suppressed.

  As described above, in the present embodiment, in accordance with the characteristics of the wafer W to be processed and the like, in the present embodiment, the modified layer formed in the direction along the first division line L1 and the second division The modified layer formed in the direction along the line L2 can be set at a desired position with high accuracy.

  Note that the present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Laser processing apparatus 10 Chuck table 10a Holding surface 20 X-axis moving means 30 Y-axis moving means 50 Laser beam irradiation means 60 Imaging means 100 Control means 101 Storage part (storage means)
102 landmark control unit 103 scheduled processing line calculation unit 110 display panel (display means)
D Device K Plan processing line L1 First planned division line L2 Second planned division line LK Modified layer formation position M Mark part MP Mark PS Start point PE End point W Wafer Wa Surface

Claims (3)

A first scheduled dividing line extending in a first direction and a second scheduled dividing line extending in a direction intersecting with the first direction are set, and the first dividing line and the second dividing line are set . A device is formed in a region defined by the scheduled line, and a laser beam is applied to a wafer having a region where the start point or the end point of the intermittently formed first scheduled line is connected to the second scheduled line. A laser processing apparatus that forms a modified layer along the first planned dividing line and the second planned dividing line inside the wafer,
A chuck table for holding the wafer on a holding surface,
A laser beam irradiating means for irradiating the wafer held on the chuck table with a laser beam having a wavelength having transparency to the wafer,
Moving means for relatively moving the chuck table and the laser beam irradiation means,
Imaging means for imaging the wafer held on the chuck table;
Storage means for storing processing conditions for processing the wafer, and storing a formation position of a modified layer, which is a position where a modified layer is to be formed, as the processing conditions ;
Display means for displaying the formation position of the modified layer stored in the storage means as the processing condition as a planned processing line, superimposed on the captured image captured by the imaging means ,
When the display unit displays a region where the start point or the end point of the first scheduled line imaged by the imaging unit is connected to the second scheduled line, the display unit already stores the position where the modified layer is formed. When there is at least one of the first planned division line and the second planned division line, the planned processing line is imaged by the imaging unit along a position where the modified layer is to be formed. is at least displayed over the one of the first dividing lines and the second dividing line,
The position of the starting point or the end point of the modified layer formed on the first scheduled dividing line or the second scheduled dividing line is set to the second dividing line or the first scheduled dividing line. A laser processing apparatus characterized in that it can be set according to the position of the modified layer.   2. The laser processing apparatus according to claim 1, wherein the display unit displays the set scheduled processing line, and is capable of correcting a start point or an end point of the set scheduled processing line. 3.   The display means includes: a target for designating an irradiation position of the laser beam by the laser beam irradiation means with respect to the second planned division line when the planned processing line is displayed so as to overlap the first planned division line. The laser processing apparatus according to claim 1, wherein a hairline, which is a line, is displayed so as to be superimposed on the second scheduled division line.

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